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1.
Artículo en Inglés | MEDLINE | ID: mdl-20388551

RESUMEN

Koinobiont parasitoids use several strategies to regulate the host's physiological processes during parasitism. Although many aspects of host-parasitoid interactions have been explored, studies that attempted to assess the effects of parasitism on the availability of inorganic elements in the host are virtually nonexistent. Therefore, we aimed to evaluate the effects of parasitism on the concentrations of inorganic elements in the fat bodies of larvae of Diatraea saccharalis (Lepidoptera: Crambidae) during the development of the parasitoid Cotesia flavipes (Hymenoptera: Braconidae), by using total reflection X-ray fluorescence (TXRF). TXRF analysis allowed comparisons of the changes in the availability of the elements P, S, K, Ca, Cr, Fe, Ni, Cu, and Zn in the fat body tissues of D. saccharalis larvae parasitized by C. flavipes. Overall, the concentration of inorganic elements was higher early in parasitoid development (1 and 3days after parasitism) compared to non-parasitized larvae, but much lower towards the end of parasitoid development (7 and 9days after parasitism). Ca, K, and S were reduced after the fifth day of parasitism, which affected the total abundance of inorganic elements observed in the fat bodies of the parasitized hosts. The regulatory mechanisms or pathological effects related to the observed variation of the host inorganic elements induced by the parasitoid remain unknown, but there might be a strategy to make these elements available to the parasitoid larvae at the end of their development, when higher metabolic activity of the host fat body is required to sustain parasitoid growth. The observed variation of the host's inorganic elements could also be related to the known effects of parasitism on the host's immune response.


Asunto(s)
Elementos Químicos , Cuerpo Adiposo/química , Himenópteros/fisiología , Lepidópteros/parasitología , Animales , Larva/química , Larva/parasitología , Lepidópteros/química
2.
Genet Mol Res ; 9(1): 231-8, 2010 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-20198578

RESUMEN

Some herbicides are suspected of promoting teratogenic, carcinogenic and mutagenic events. Detection of induced mitotic crossing-over has proven to be an indirect way of testing the carcinogenic properties of suspicious substances, because mitotic crossing-over is involved in the multistep process of carcinogenesis. We examined mitotic crossing-over induced by two commercial herbicides (diuron and trifluralin) in diploid strains of Aspergillus nidulans based on the homozygotization index. Low doses (2.5 microg/mL) of diuron were sufficient to increase the mean homozygotization index in 2.1 and 11.3 times for UT448//UT196 and Dp II-I//UT196, respectively, whereas the same dose of trifluralin increased this mean only 1.2 (UT448//UT196) and 3.5 (Dp II-I//UT196) times, respectively. The lower homozygotization index value found for trifluralin could be due to its interference with mitotic crossing-over in eukaryotic cells. We concluded that the diploid Dp II-I//UT196 of A. nidulans is more sensitive to organic compounds than UT448//UT196; these compounds cause recombinational events at a greater frequency in the latter diploid. This system holds promise as an initial test for carcinogenicity of organic compounds, including herbicides.


Asunto(s)
Aspergillus nidulans/efectos de los fármacos , Aspergillus nidulans/genética , Intercambio Genético/efectos de los fármacos , Diploidia , Herbicidas/toxicidad , Mitosis/efectos de los fármacos , Diurona/toxicidad , Ligamiento Genético , Genotipo , Homocigoto , Trifluralina/toxicidad
3.
Genet Mol Res ; 8(2): 404-13, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19440976

RESUMEN

Mercury (Hg) pollution is one of the most serious environmental problems. Due to public concern prompted by the symptoms displayed by people who consumed contaminated fish in Minamata, Japan in 1956, Hg pollution has since been kept under constant surveillance. However, despite considerable accumulation of knowledge on the noxious effects of ingested or inhaled Hg, especially for humans, there is virtually nothing known about the genotoxic effects of Hg. Because increased mitotic crossing over is assumed to be the first step leading to carcinogenesis, we used a sensitive short-term test (homozygotization index) to look for DNA alterations induced by Hg fumes. In one Aspergillus nidulans diploid strain (UT448//UT184), the effects of the Hg fumes appeared scattered all over the DNA, causing 3.05 times more recombination frequencies than the mean for other strains. Another diploid (Dp II-I//UT184) was little affected by Hg. This led us to hypothesize that a genetic factor present in the UT184 master strain genome, close to the nicB8 genetic marker, is responsible for this behavior. These findings corroborate our previous findings that the homozygotization index can be used as a bioassay for rapid and efficient assessment of ecotoxicological hazards.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Aspergillus nidulans/efectos de los fármacos , Aspergillus nidulans/genética , Células Eucariotas/efectos de los fármacos , Células Eucariotas/metabolismo , Mercurio/toxicidad , Pruebas de Mutagenicidad/métodos , Cromosomas Fúngicos/genética , Intercambio Genético/efectos de los fármacos , ADN de Hongos/genética , Diploidia , Monitoreo del Ambiente
4.
J Appl Microbiol ; 105(6): 2153-60, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19016976

RESUMEN

AIMS: To evaluate the ability of Streptomyces sp. (strain ASBV-1) to restrict aflatoxin accumulation in peanut grains. METHODS AND RESULTS: In the control of many phytopathogenic fungi the Streptomyces sp. ASBV-1 strain showed promise. An inhibitory test using this strain and A. parasiticus was conducted in peanut grains to evaluate the effects of this interaction on spore viability and aflatoxin accumulation. In some treatments the Streptomyces sp ASBV-1 strain reduced the viability of A. parasiticus spores by c. 85%, and inhibited aflatoxin accumulation in peanut grains. The values of these reductions ranged from 63 to 98% and from 67% to 96% for aflatoxins B(1) and G(1), respectively. CONCLUSIONS: It was demonstrated that Streptomyces sp. ASBV-1 is able to colonize peanut grains and thus inhibit the spore viability of A. parasiticus, as well as reducing aflatoxin production. SIGNIFICANCE AND IMPACT OF THE STUDY: The positive finding for aflatoxin accumulation reduction in peanut grains seems promising and suggests a wider use of this actinobacteria in biological control programmes.


Asunto(s)
Aflatoxinas/análisis , Arachis/química , Aspergillus/fisiología , Contaminación de Alimentos/prevención & control , Streptomyces/fisiología , Arachis/microbiología , Arachis/fisiología , Cromatografía en Capa Delgada , Grano Comestible , Espectrometría de Masas/métodos , Esporas Fúngicas/fisiología
5.
Genet Mol Res ; 7(2): 467-75, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18561380

RESUMEN

As a contribution towards detecting the genetic effects of low doses of genotoxic physical agents, this paper deals with the consequences of low-dose X-rays in the Aspergillus nidulans genome. The irradiation doses studied were those commonly used in dental clinics (1-5 cGy). Even very low doses promoted increased mitotic crossing-over frequencies in diploid strains heterozygous for several genetic markers including the ones involved in DNA repair and recombination mechanisms. Genetic markers of several heterozygous strains were individually analyzed disclosing that some markers were especially sensitive to the treatments. These markers should be chosen as bio-indicators in the homozygotization index assay to better detect the recombinogenic/carcinogenic genomic effects of low-dose X-rays.


Asunto(s)
Aspergillus nidulans/efectos de la radiación , Intercambio Genético/efectos de la radiación , Mitosis/efectos de la radiación , Rayos X , Aspergillus nidulans/genética , Intercambio Genético/genética , Daño del ADN , Diploidia , Relación Dosis-Respuesta en la Radiación , Homocigoto , Mitosis/genética , Pruebas de Mutagenicidad
6.
Genet. mol. res. (Online) ; 7(2): 467-475, 2008.
Artículo en Inglés | LILACS | ID: lil-640991

RESUMEN

As a contribution towards detecting the genetic effects of low doses of genotoxic physical agents, this paper deals with the consequences of low-dose X-rays in the Aspergillus nidulans genome. The irradiation doses studied were those commonly used in dental clinics (1-5 cGy). Even very low doses promoted increased mitotic crossing-over frequencies in diploid strains heterozygous for several genetic markers including the ones involved in DNA repair and recombination mechanisms. Genetic markers of several heterozygous strains were individually analyzed disclosing that some markers were especially sensitive to the treatments. These markers should be chosen as bio-indicators in the homozygotization index assay to better detect the recombinogenic/carcinogenic genomic effects of low-dose X-rays.


Asunto(s)
Aspergillus nidulans/efectos de la radiación , Mitosis/efectos de la radiación , Intercambio Genético/efectos de la radiación , Rayos X , Aspergillus nidulans/genética , Diploidia , Daño del ADN , Homocigoto , Pruebas de Mutagenicidad , Mitosis/genética , Relación Dosis-Respuesta en la Radiación , Intercambio Genético/genética
7.
J. venom. anim. toxins incl. trop. dis ; 13(2): 527-543, 2007. graf, tab
Artículo en Inglés | LILACS, Sec. Est. Saúde SP | ID: lil-452845

RESUMEN

Total RNA from lipopolysaccharide (LPS)-stimulated rat macrophages used to treat protoplasts from an Aspergillus nidulans strain originated the RT2 regenerated strain, whose culture supernatant showed anti-inflammatory activity in Wistar rats. The protein fraction presenting such anti-inflammatory activity was purified and biochemically identified. The screening of the fraction responsible for such anti-inflammatory property was performed by evaluating the inhibition of carrageenan-induced paw edema in male Swiss mice. Biochemical analyses of the anti-inflammatory protein used chromatography, carbohydrates quantification of the protein sample, amino acids content analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Total sugar quantification revealed 32 percent glycosylation of the protein fraction. Amino acid analysis of such fraction showed a peculiar pattern presenting 29 percent valine. SDS-PAGE revealed that the protein sample is pure and its molecular weight is about 40kDa. Intravenous injection of the isolated substance into mice significantly inhibited carrageenan-induced paw edema. The isolated glycoprotein decreased carrageenan-induced paw edema in a prostaglandin-dependent phase, suggesting an inhibitory effect of the isolated glycoprotein on prostaglandin synthesis.


Asunto(s)
Ratones , Animales , Antiinflamatorios , Aspergillus nidulans , Aspergilosis , Glicoproteínas
9.
Psychother Psychosom ; 75(6): 376-83, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17053339

RESUMEN

BACKGROUND: It is speculated that clinical samples do not fully reflect the characteristics of eating disorders (EDs) as they are in the general population, especially in their lowest range of severity. The present article reports the prevalence of EDs in a community sample aged >14 years, their clinical and psychopathological features, and their course and outcome on naturalistic grounds. METHODS: The Sesto Fiorentino Study is a three-phase community-based survey where 2,355 out of 2,500 people representative of the population aged >14 years living in Sesto Fiorentino were evaluated by their own general practitioner using the Mini International Neuropsychiatric Interview plus six additional questions. All those who had positive results plus a probability sample of the non-cases were re-interviewed by psychiatrists using the Florence Psychiatric Interview. The subjects who reported ED symptoms were subsequently administered the Eating Disorder Examination (12th edition). RESULTS: Overall, the lifetime prevalence of EDs was 1.21%. More precisely, 0.42% had anorexia nervosa, 0.32% bulimia nervosa, 0.32% binge eating disorder and 0.32% eating disorder not otherwise specified. All the subjects suffering from an ED fulfilled diagnostic criteria for at least another DSM-IV axis I psychiatric disorder. At the moment of the interview, conducted a few years (average 7 years) after the onset of the disorder, 50% had fully recovered from EDs, 26.9% were currently affected by an ED, 23.1% showed a persistent body image disturbance and/or the presence of compensatory behaviours. CONCLUSIONS: Community surveys conducted by clinicians may provide useful additional information on the psychopathological features, natural course and outcome of these disorders on naturalistic grounds.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Adolescente , Antropometría , Índice de Masa Corporal , Áreas de Influencia de Salud , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Quimioterapia , Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Humanos , Italia/epidemiología , Prevalencia , Psicoterapia , Índice de Severidad de la Enfermedad , Trastornos Somatomorfos/epidemiología , Trastornos Somatomorfos/psicología , Encuestas y Cuestionarios , Resultado del Tratamiento
10.
Eat Weight Disord ; 9(3): 228-31, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15656019

RESUMEN

UNLABELLED: The purpose of this study was to determine the validity of the Eating Disorder Examination 12.0D (EDE) when administered retrospectively. METHODS: Twenty-five female patients suffering from an eating disorder [(10 with anorexia nervosa (AN), 10 with bulimia nervosa (BN), 5 with eating disorders not otherwise specified (EDNOS)] were investigated using the EDE at the time of the first referral to our outpatient ward (T1). Afterwards (mean 1.4 +/- 0.6 years later) each patient was administered again the EDE by the same assessor (T2). At this time the interviewer asked the patients to answer the questions referring to the symptoms and behaviours at the time of the first interview. RESULTS: Test-retest correlation factors were 0.7 or greater for all subscales of the EDE (p < 0.0001) and 0.5 or greater for every single item of the EDE (p < 0.001), except for EDE 1.5 (snack after dinner) and EDE 9A.6 (maximum time free from objective bulimic episodes in the last two months). DISCUSSION: Our results provide evidence that the EDE 12.0D is a reliable interview even when administered retrospectively, suggesting the use of this instrument for the retrospective assessment of eating disorders.


Asunto(s)
Trastornos de Alimentación y de la Ingestión de Alimentos/diagnóstico , Entrevista Psicológica , Adulto , Bulimia/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
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